Police may stop a person if they have a reasonable suspicion that the person has committed or is about to commit a crime, and may frisk the suspect for weapons if they have reasonable suspicion that the suspect is armed and dangerous, without violating the Fourth Amendment prohibition on unreasonable searches and seizures. Supreme Court of Ohio affirmed.

For their own protection, police may perform a quick surface search of the person’s outer clothing for weapons if they have reasonable suspicion that the person stopped is armed. This reasonable suspicion must be based on "specific and articulable facts" and not merely upon an officer's hunch. This permitted police action has subsequently been referred to in short as a "stop and frisk," or simply a "Terry frisk". The Terry standard was later extended to temporary detentions of persons in vehicles, known as traffic stops; see Terry stop for a summary of subsequent jurisprudence.

The rationale behind the Supreme Court decision revolves around the understanding that, as the opinion notes, "the exclusionary rule has its limitations." The meaning of the rule is to protect persons from unreasonable searches and seizures aimed at gathering evidence, not searches and seizures for other purposes (like prevention of crime or personal protection of police officers).

On October 31, 1963, while on a downtown beat which he had been patrolling for many years, Cleveland Police Department Detective Martin McFadden, aged 62,[2] saw two men, John W. Terry and Richard Chilton, standing on a street corner at 1276 Euclid Avenue and acting in a way the officer thought was suspicious. Detective McFadden, who was well-known on the Cleveland police force for his skill in apprehending pickpockets,[2] observed the two proceed alternately back and forth along an identical route, pausing to stare in the same store window. Each completion of the route was followed by a conference between the two on a corner. The two men repeated this ritual alternately between five and six times apiece—in all, roughly a dozen trips. After one of these trips, they were joined by a third man (Katz) who left swiftly after a brief conversation. Suspecting the two men of "casing a job, a stick-up", detective McFadden followed them and saw them rejoin the third man a couple of blocks away in front of a store.

The plainclothes officer approached the three, identified himself as a police officer, and asked their names. The men "mumbled something", whereupon McFadden spun Terry around, patted down his outside clothing, and felt a pistol in his overcoat pocket. He reached inside the overcoat pocket, but was unable to remove the gun. The officer ordered the three into the store. He removed Terry's overcoat, took out a revolver, and ordered the three to face the wall with their hands raised. He patted down the outer clothing of Chilton and Katz and seized a revolver from Chilton's outside overcoat pocket. He did not put his hands under the outer garments of Katz (since he discovered nothing in his pat-down which might have been a weapon), or under Terry's or Chilton's outer garments until he felt the guns. The three were taken to the police station. Terry and Chilton were subsequently charged with carrying concealed weapons.

The defense of the charged individuals moved to suppress the use of the seized weapons as evidence on grounds that the search and subsequent seizure were a violation of the Fourth Amendment to the United States Constitution. Though the trial court rejected the prosecution theory that the guns had been seized during a search incident to a lawful arrest, the court denied the motion to suppress and admitted the weapons into evidence on the ground that the officer had cause to believe that Terry and Chilton were acting suspiciously, that their interrogation was warranted, and that the officer for his own protection had the right to pat down their outer clothing having reasonable cause to believe that they might be armed. The trial court made a distinction between an investigatory "stop" and an arrest, and between a "frisk" of the outer clothing for weapons and a full-blown search for evidence of crime.

Terry and Chilton were found guilty, an intermediate appellate court affirmed the conviction, and the Ohio State Supreme Court dismissed the appeal on the ground that "no substantial constitutional question" was involved.

Chief Justice Warren's opinion for the Court began by reciting first principles. The Fourth Amendment protects "people, not places", against "unreasonable searches and seizures". The question the Court confronted was whether "in all the circumstances of this on-the-street encounter", Terry's reasonable expectation of privacy had been impermissibly invaded.

The procedure called "stop and frisk" was controversial. Police argue that they require a certain flexibility in dealing with quickly evolving and potentially dangerous situations that arise during routine patrol of the streets. On the other hand, those suspicious of giving the police broad investigatory power contended that the police should not be able to assert their authority over citizens without some specific justification upon intrusion into protected personal security, coupled with judicial oversight to ensure that the police do not routinely abuse their authority. For the Court, however, the question was not the propriety of the police actions in the abstract but the admissibility of the evidence obtained through that police action. "In our system evidentiary rulings provide the context in which the judicial process of inclusion and exclusion approves some conduct as comporting with constitutional guarantees and disapproves other actions by state agents." For this purpose the exclusionary rule of Mapp v. Ohio, 367 U.S.643 (1961), had evolved and been applied against both state and federal agents.

Thus the question was not whether the stop-and-frisk procedure was proper by itself, but whether the exclusionary rule was an appropriate deterrent of police misconduct during such encounters.

“

Proper adjudication of cases in which the exclusionary rule is invoked demands a constant awareness of these limitations. The wholesale harassment by certain elements of the police community, of which minority groups, particularly Negroes, frequently complain, will not be stopped by the exclusion of any evidence from any criminal trial. Yet a rigid and unthinking application of the exclusionary rule, in futile protest against practices which it can never be effectively used to control, may exact a high toll in human injury and frustration of efforts to prevent crime.

”

— Terry v. Ohio, 392 U.S. 1, 14–15

In view of these concerns, the Court next asked whether it is "always unreasonable for a policeman to seize a person and subject him to a limited search for weapons unless there is probable cause for an arrest."

The Supreme Court first had to determine, for purposes of the Fourth Amendment, when is a person "seized" and what constitutes a "search". The Court rejected the idea that a "stop and frisk" could categorically never be a search or seizure subject to the protection of the Fourth Amendment. Instead, it made room for the idea that some police action short of a traditional arrest could constitute a seizure—that is, "whenever a police officer accosts an individual and restrains his freedom to walk away, he has 'seized' that person." The Court also noted that "... it is nothing less than sheer torture of the English language to suggest that a careful exploration of the outer surfaces of a person's clothing all over his or her body in an attempt to find weapons is not a 'search.' "

Thus, when the police detective took hold of Terry and patted him down on that Cleveland street, the detective "seized" Terry and subjected him to a "search" within the meaning of the Fourth Amendment. But the Fourth Amendment protects only against unreasonable searches and seizures, so the Court next had to determine whether Terry’s seizure and search were "reasonable".

The Court assessed the reasonableness of the police activity here by comparing it to activity that would ordinarily require a warrant. "[I]n justifying the particular intrusion the police officer must be able to point to specific and articulable facts which, taken together with rational inferences from those facts, reasonably warrant the intrusion." In a situation where the police obtained a warrant, they would have brought these facts and inferences to the attention of a judicial officer (e.g., judge or magistrate) before embarking on the actions in question. Post hoc judicial review of police activity is equally facilitated by these facts and inferences.

The Court also emphasized that the test standard courts should employ is an objective one. "Would the facts available to the officer at the moment of the seizure or the search warrant a man of reasonable caution in the belief that the action taken was appropriate?" Lesser evidence would mean that the Court would tolerate invasions on the privacy of citizens supported by mere hunches—a result the Court would not tolerate. Moreover,

simple " 'good faith on the part of the arresting officer is not enough.' ... If subjective good faith alone were the test, the protections of the Fourth Amendment would evaporate, and the people would be 'secure in their persons, houses, papers, and effects,' only in the discretion of the police." — quoting Beck v. Ohio, 379 U.S.89 (1964)

The reasonableness inquiry takes into account the "nature and extent of the governmental interests involved", including the general interest in crime prevention, the officer's specific concern for his own safety, the citizen's interest in his own privacy and dignity, and the extent to which the particular search in question intruded upon those interests. "Our evaluation of the proper balance that has to be struck in this type of case leads us to conclude that there must be a narrowly drawn authority to permit a reasonable search for weapons for the protection of the police officer, where he has reason to believe that he is dealing with an armed and dangerous individual, regardless of whether he has probable cause to arrest the individual for a crime."

Even searches that start out as reasonable may "violate the Fourth Amendment by virtue of their intolerable intensity and scope." Thus, the scope of the search must be justified by the circumstances that led the police to undertake it in the first place.

These principles led the Court to conclude that the evidence found on Terry's person was properly admitted because the search was reasonable. The detective had observed Terry and his companions acting in a manner he took to be a preface to a stick-up. A reasonable person in the detective's position would have thought that Terry was armed and thus presented a threat to his safety while he was investigating the suspicious behavior he was observing. The events he had witnessed made it reasonable for him to believe that either Terry or his cohorts were armed. "The record evidences the tempered act of a policeman who in the course of an investigation had to make a quick decision as to how to protect himself and others from possible danger, and took limited steps to do so."

The police detective here limited his search to the outer surfaces of Terry's clothing. Thus, the search was reasonably related in scope to the concern for his own safety that justified the stop from the beginning. Accordingly, the Court concluded that the revolver found on Terry's person was properly admitted into evidence.

The sole justification for the search is protection of the officer and public[edit]

The Ohio Court of Appeals allowed the search, but made it clear that such a search was limited to discovering dangerous weapons that could be used against the officer, as Chief Justice Warren noted:

"In this case, for example, the Ohio Court of Appeals stated that 'we must be careful to distinguish that the "frisk" authorized herein includes only a "frisk" for a dangerous weapon. It by no means authorizes a search for contraband, evidentiary material, or anything else in the absence of reasonable grounds to arrest. Such a search is controlled by the requirements of the Fourth Amendment, and probable cause is essential.' " (392 U.S. 1, at 16, Fn 12, quoting State v. Terry, 5 Ohio App. 2d 122, at 130)

Chief Justice Warren later made it clear that this was also the opinion of the Court:

"The sole justification of the search ... is the protection of the police officer and others nearby, and it must therefore be confined in scope to an intrusion reasonably designed to discover guns, knives, clubs, or other hidden instruments for the assault of the police officer."[3]

"... it is simply fantastic to urge that such a procedure performed in public by a policeman while the citizen stands helpless, perhaps facing a wall with his hands raised, is a 'petty indignity.' It is a serious intrusion upon the sanctity of the person, which may inflict great indignity and arouse strong resentment, and it is not to be undertaken lightly."[4]

"There is nothing in the Constitution which prevents a policeman from addressing questions to anyone on the streets. Absent special circumstances, the person approached may not be detained or frisked but may refuse to cooperate and go on his way. However, given the proper circumstances, such as those in this case, it seems to me the person may be briefly detained against his will while pertinent questions are directed to him. Of course, the person stopped is not obliged to answer, answers may not be compelled, and refusal to answer furnishes no basis for an arrest, although it may alert the officer to the need for continued observation."[5]

With regard to the lack of obligation to respond when detained under circumstances of Terry, this opinion came to be regarded as persuasive authority in some jurisdictions, and the Court cited these remarks in dicta in Berkemer v. McCarty, 468 U.S.420 (1984), at 439. However, in Hiibel v. Sixth Judicial District Court of Nevada, 542 U.S.177 (2004), the Court held that neither of these remarks was controlling in a situation where a state law required a detained person to identify himself.

"We hold today that the police have greater authority to make a 'seizure' and conduct a 'search' than a judge has to authorize such action. We have said precisely the opposite over and over again."[6]

"To give the police greater power than a magistrate is to take a long step down the totalitarian path. Perhaps such a step is desirable to cope with modern forms of lawlessness. But if it is taken, it should be the deliberate choice of the people through a constitutional amendment."[7]

According to this case, The 4th Amendment to the Constitution of the United States of America states that 1. A search cannot be unreasonable and 2. That there needs to be reasonable cause or individual suspicion for a search to be conducted.

The Terry doctrine was markedly extended in the 2004 case of Hiibel v. Sixth Judicial District Court of Nevada, 542 U.S.177 (2004), in which the Supreme Court held that a state law requiring the suspect to identify himself during a Terry stop did not violate the Fourth Amendment prohibitions of unreasonable searches and seizures or the Fifth Amendment privilege against self-incrimination. The Court did not legalize this process in all states but instead left it up to the states to decide whether they would pass such laws. So far 24 states have passed such laws.

The Court most recently cited Terry v. Ohio in Arizona v. Johnson. In that 2009 case, the Court ruled 9–0 in favor of further expanding Terry, granting police the ability to frisk an individual in a stopped vehicle if there is reasonable suspicion to believe the individual is armed and dangerous. This fulfills only the second prong of Terry (the first prong—reasonable suspicion that a crime has, is, or will be committed—is fulfilled by whatever traffic violation prompted the pull-over). According to Whren v. United States, any traffic violation, no matter how small, is legitimate basis for a traffic stop.